An image of the galaxy comprising red dwarf Gliese 581 and the earth-like planet Bebo is trying to contact. Photograph: AFP

Bebo and the TV company behind Wife Swap have teamed up with one of the world's experts in interstellar radio communication, Dr Alexander Zaitsev, to beam 500 messages from users into space in a digital time capsule.

Dr Zaitsev will use a Ukrainian radio telescope, normally used to identify and track asteroids that pose a threat to Earth, to beam the messages to a planet orbiting the star Gliese 581c - 20 light years from Earth - because it is believed to be capable of supporting life.

The Message From Earth project, which launches on August 4, will invite Bebo users, celebrities and politicians to submit messages and pictures that "consider the planet from a fresh perspective" and raise awareness of environmental pressures on our planet.

Whether there is intelligent life elsewhere in the universe remains "one of the greatest unanswered questions", said Dr Zaitsev.

But he added that it would be exciting to see how young people chose to represent humanity and the planet.

"I understand that in the majority of cases these messages may be naïve, but I also hope that we will receive a creative and fresh look at the subject," Dr Zaitsev said.

Conceived by Oli Madgett of RDF Digital, a subsidiary of Wife Swap producer RDF Media, the project claims to be the first to democratically select content to be transmitted into space.

Users can post entries and vote for the best ones on a dedicated Bebo page. The winning 500 will be sent into space.

The vote runs from August 4 until September 30. The digital time capsule with the 500 selected messages will be transmitted on October 9.

RDF is covering the £20,000 data cost of the four-and-a-half-hour transmission from the National Space Agency in Ukraine, sending the messages on the 120 trillion-mile journey to Gliese 581c.

Madgett is a former interactive producer on Big Brother, Wife Swap and Shipwrecked.

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